We discussed the time-dependence of fluorescent emission anisotropy of a cylindrical probe in membrane vesicles. We showed that, if the motion of the probe were described as diffusion in an anisotropic environment, it would be possible to determine not only the second-rank but also the fourth-rank orientational order parameter from the decay of the fluorescence anisotropy. The approximations involved were based on an interpolation of short-time and long-time behavior of the relevant correlation functions. A general expression was derived for the time dependence of the fluorescence anisotropy in closed form, which applies to any particular distribution model. It was shown to be in good agreement with previously reported results for the cone model and the Gaussian model. Finally, the applicability of the theory to time-resolved and differential phase fluorescence depolarization experiments was discussed.

Metallic-glass formation by solid-state reactions has been observed in multilayer Zr-Co diffusion couples and studied by cross-sectional transmission electron microscopy. Planar growth of a Corich amorphous phase proceeds from each interface of the unreacted sample, thus consuming the Co layers at a higher rate. Further annealing results eventually in a reaction of the Co-rich glassy phase with remaining Zr. Because of the high diffusivity of the Co in the amorphous phase, Kirkendall voids are formed during this homogenizing process and are lined up with the periodicity of the original layered structure.

The aggregation of proteins in membranes accompanied by a higher elasticity of the membrane in the vicinity of the proteins and a shift of the crystalline–liquid crystalline phase transition to higher temperatures is shown to be caused by an indirect interaction between the ’’annuli’’ of proteins. In the neighborhood of proteins the order-parameter fluctuations will be decreased, building a region of relative stability, which lowers the free energy of the system. On the base of a linear response approximation an effective potential is defined and an explicit expression for the distance-dependent interaction of two cylindrical model proteins is derived.

Cladosporin, a natural product known for decades, has recently been discovered to display potent and selective antiplasmodial activity by inhibition of lysyl‐tRNA synthetase. It was subjected to a panel of oxidative biotransformations with one fungal and two actinomycetes strains, as well as a triple mutant bacterial CYP102A1, yielding eight, mostly hydroxylated, derivatives. These new compounds covered a wide chemical space and contained two pairs of epimers in the tetrahydropyran ring. Although less potent than the parent compound, all analogues showed activity in a cell‐based synthetase assay, thus demonstrating uptake and on‐target activity in living cells with varying degrees of selectivity for the enzyme lysyl‐tRNA synthetase from Plasmodium falciparum and highlighting sites suitable for synthesis of future cladosporin analogues. Compounds with adjacent hydroxy functions showed different MS/MS fragmentation that can be explained in terms of an, in some cases, regioselective loss of water followed by a retro‐Diels–Alder reaction.

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